Type YF8GNC: Immersion heater thermostats



-Equipment requesting a very strong resistance to water ingress. The transparent cover allows to visualize the set point and the 2 pilot lights

Fully wired sub assembly for use on  immersion heater elements, 1”1/2 or M45x2 with double thread or rotation ring.

Applications in usual industrial applications and environments,  non-hazardous areas.


Housing: Protection class IP 66 upon EN 60529 (waterproof spray water under high pressure and sea splashes, totally dust tight). Body in black PA66, fiber glass reinforced. The transparent polycarbonate cover can be unscrewed by hand, but it is also possible to use a hook spanner.  A removable adapter is screwed at the bottom of the enclosure. It fits the usual immersion heater fittings. . Mechanical impact resistance : IK10. High UV resistance.

Set point adjustment:  By °C printed knob. All types have an adjustable rotation limit system located inside the knob that allows reducing the set point adjustment span. °F printed knobs available as an option.

Action: Temperature control. On-Off action

Sensing element: Liquid expansion bulb and capillary. The bulb and the capillary go out by the bottom of  the enclosure to fit in the heater pocket.

Pilot lights: One pilot light visualizes the thermostat contact output position. The other visualizes the power supply input. Phase and line electrical supply is mandatory for these pilot lights.

Set point adjustment ranges: 0-60°C (32-140°F); 0-90°C (32-195°F); 30-90°C (85-195°F); 30-110°C (85-230°F).

Cable input and output: Two M20 cable glands, built-in black PA66. One of them is closed.

Electrical connections:  Inside, on screw terminal connection block. It is possible to connect 2 wires 1.5mm² on each terminal.

Earthing:  Internal screw terminal and wire with round hole terminal for the immersion heater.

Mounting: By the immersion heater thread or by 2 legs with holes for screws dia. 4 to 5 mm, 114  mm distance

Identification: Identification label on backside

Contact: SPDT

Electrical rating, resistive loads:

 –Open on temperature rise contact (C-1)

16A 250V, 50 ~60Hz: >100000 cycles,

20A 250V, 50 ~60Hz: ≥ 50000 cycles,

10A 400V, 50 ~60Hz: ≥ 50000 cycles.

-Close on temperature rise contact (C-2): 6A 250V 50 ~60Hz: >100000 cycles

Electrical rating, inductive loads:

 –Open on temperature rise contact (C-1): 2.6A 250V, 50 ~60Hz: >100000 cycles

-Close on temperature rise contact (C-2):0.6A 250V 50 ~60Hz: >100000 cycles. 

Minimum storage temperature: -35°C (-30°F)

Maximum ambient temperature: 60°C (140°F)

For more technical information ask 8G thermostat technical data sheet.



2D&3D Drawing

Main references

Temperature range

°C (°F)

References  Capillary length (C, mm) Bulb diameter

(D1, mm)

Bulb length

(L1, mm)


°C (°F)

Max temperature on bulb °C (°F)
0-60°C (32-140°F) YF8GNC00060026ZJ 200 6 86±5 2.5±1°C (4,5±1,8°F)

80°C (176°F)

0-60°C (32-140°F)

YF8GNC00060036ZJ 300 6 86±5 2.5±1°C (4,5±1,8°F) 80°C (176°F)
0-60°C (32-140°F) YF8GNC00060046ZJ 400 6 86±5 2.5±1°C (4,5±1,8°F)

80°C (176°F)

0-60°C (32-140°F)

YF8GNC00060056ZJ 500 6 86±5 2.5±1°C (4,5±1,8°F) 80°C (176°F)
0-90°C (32-195°F) YF8GNC00090026ZJ 200 6 98±5 2.5±1°C (4,5±1,8°F)

120°C (250°F)

0-90°C (32-195°F)

YF8GNC00090036ZJ 300 6 98±5 2.5±1°C (4,5±1,8°F) 120°C (250°F)
0-90°C (32-195°F) YF8GNC00090046ZJ 400 6 98±5 2.5±1°C (4,5±1,8°F)

120°C (250°F)

0-90°C (32-195°F)

YF8GNC00090056ZJ 500 6 98±5 2.5±1°C (4,5±1,8°F) 120°C (250°F)
30-90°C (85-195°F) YF8GNC30090026ZJ 200 6 98±5 2.5±1°C (4,5±1,8°F)

120°C (250°F)

30-90°C (85-195°F)

YF8GNC30090036ZJ 300 6 98±5 2.5±1°C (4,5±1,8°F) 120°C (250°F)
30-90°C (85-195°F) YF8GNC30090046ZJ 400 6 98±5 2.5±1°C (4,5±1,8°F)

120°C (250°F)

30-90°C (85-195°F)

YF8GNC30090056ZJ 500 6 98±5 2.5±1°C (4,5±1,8°F) 120°C (250°F)
30-110°C (85-230°F) YF8GNC30110026ZJ 200 6 86±5 2.5±1°C (4,5±1,8°F)

140°C (284°F)

30-110°C (85-230°F)

YF8GNC30110036ZJ 300 6 86±5 2.5±1°C (4,5±1,8°F) 140°C (284°F)
30-110°C (85-230°F) YF8GNC30110046ZJ 400 6 86±5 2.5±1°C (4,5±1,8°F)

140°C (284°F)

30-110°C (85-230°F)

YF8GNC30110056ZJ 500 6 86±5 2.5±1°C (4,5±1,8°F)

140°C (284°F)

°F printing: replace last character (J) by K